Vascular Injury

Peripheral vascular injury

Clinical

Hard signs

· physical findings of arterial occlusion

— pain, pallor, pulselessness, poikilothermia, paralysis, paraesthesia

· arterial bleeding

· rapidly expanding haematoma

· palpble thrill or bruit

Soft signs

· proximity of wound to a major vessel

· history of arterial bleeding at the accident site

· small nonpulsatile haematoma

· neurological deficit in the limb

· if hard signs are present immediate operation with intra-operative arteriography is required

· if soft signs only then ABI should be done if <1.0 then arteriogram obtained

· results of arteriography will be

— Normal ® observation

— Minimal injury ® observe +/- repeat the angio

— Major injury ® operation or embolisation or stent

Surgical approach

· expose the entire limb

· expose a groin for vein harvesting

· temporary proximal control can be gained with placement of a balloon catheter

· control is gained with clamps proximal and distal

· Fogarty balloon used to clear the vessel proximally and distally and heparinised saline used to flush the lumens

· systemic heparin can be used if there is no contraindication

· temporary shunting should be considered in the very ischaemic limb where orthapedic injuries need to be done or there are other lifethreatening injuries

— early fasciotomy

— use of contralateral saphenous vein

— repair of major venous injuries

— completion arteriography

— adequete soft tissue cover (muscle flaps as needed)

Trauma 35

· consider giving mannitol prior to revascularisation (as a free radicle scavenger) to decrease

reperfusion injury

· pressures >25mmHg in the compartment with signs mandates fasciotomy; >25mmHg without signs

should also be decompressed

· in the presence of avulsed nerves, early amputation may be best - psychological impact needs to be taken into account

Repair

· lateral repair

· end to end

· patch

· bypass graft

· autogenous vein is used preferentially

· beware of reperfusion injury - consider mannitol

Specific sites

Subclavian/ Axillary

· median sternotomy for R

· anterolaleral for L

· plus supraclavicular for distal control

· rarely the middle 1/3 of the clavicle needs to be removed

· axillary approached through an infraclavicular horizontal incision

Brachial/ Radial/ & Ulnar

· single vessel injury at the forearm can be ligated or embolized

· if palmar arch is incomplete or Allen’s test is positive then repair must be undertaken

External Iliac/ femoral

· profunda can be ligated in the precarious patient

· femoral and iliac must be repaired

· iliac approached retroperitoneal through an oblique incision 2cm above the inguinal ligament

· SFA approached a la supragenicular and groin

· arteriography for penetrating injuries on the medial thigh and close to a major vessel; lateral wound

exiting the posterior thigh can be observed

Popliteal artery

· arterial trauma occurs in

— 30% of knee dislocations

— 60% # dislocation of knee

· medial approach

· side to side or end to end anastamosis

· interposition venous graft may be necessary

Trauma 36

Venous Injury

· repair is undertaken in the stable patient

· preferably simple anastamosis

· 60% of grafts can be expected to fail but this does not affect limb salvage

· ligation may be appropriate in the face of extensive complex damage

· elevation and elastic stockings will be required

Compartment syndrome

· can be anticipated after a period of prolonged shock or arterial occlusion or crush injury

· pressures over 25mmHg mandate fasciotomy

 

Vascular injury

How do you know if a patient has an arterial injury

· Hard signs – pulsatile external bleeding, expanding or pulsatile haematoma, bruit, evidence of ischaemia (reduced or absent pulses, 6 P’s)

· Soft signs – proximity of major vascular structure to injury, adjacent nerve deficit, unexplained hypotension, stable haematoma.

· If suspicious then screen using arterial pressure index.

· In lower limb ABPI or upper limb Wrist Brachial pressure index (WBPI)

· If API >0.9 then 99% negative predictive value of significant arterial injury

· If <0.9 then 95% sensitive and 97% specific for arterial injury and CT angio should be performed. The CT angio will show extravasation, focal narrowing, obstruction, wall irregularity, false aneurym, early filling (AV fistula).

· If >0.9 and soft signs are present then perform Duplex. The duplex will detect lesions such as intimal flap, false aneurysm, AV fistula, focal narrowing which do not require surgery.

How do you control bleeding

Direct digital pressure – tourniquet occludes collaterals, clamps damage nerves.

How do you manage limb trauma with associated arterial injury

Primary survey

· A with cervical spine control

· B

· C with haemorrhage control – direct pressure over bleeding site. Inflate foley catheter in wound tract for some other sites (eg subclavian).

If massive arterial bleeding then proceed to OR for damage control.

Damage control surgery involves

· Shunting – to allow for early orthopaedic stabilization

· Ligation – external carotid, 2nd part subclavian or internal iliacs can be ligated without consequence. Single below knee vessels can be ligated. Ligate bleeding veins in damage control.

· Post-op fasciotomy either prophylactically (>3 hr ischaemia) or monitor pressures in ICU.

Check for coagulopathy, re-warm, deal with associated injuries

Secondary survey

· # or dislocations should be reduced using a temporary splint or external fixator before vascular repair as the restoration of alignment can restore circulation.

Assess for vascular injuries using API

If positive CT angio/angiography followed by exploration

· Definitive repair techniques

· Suture repair – provided vessel is not narrowed. Vessel debrided, balloon thrombo-embolecomy is performed, imtimal flaps are tacked down and vessel is sutured +/- patch angioplasty if vessel is narrowed. Completion angio.

· Bypass – vein graft is preferable.

Venous injury

Attempt to repair venous injuries as it enhances the success of associated arterial repairs even if late thrombosis occurs.

Most major veins can be ligated with exception of supra-renal IVC and portal vein.

What are the principles of arterial trauma surgery

Drape for wide exposure (including the chest for upper limb and abdomen for lower limb) to allow proximal control

Make longitudinal incisions over arteries to be explored

Dissect away from haematoma

Proximal and distal control

Debride the injured vessel and repair if possible without tension otherwise use vein interposition graft if possible